Power supply



FIG. 1 is a perspective view of a “power supply” showing our new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a front side elevational view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left side elevational view thereof; and,

FIG. 7 is a rear side elevational view thereof.

The ornamental design for a “power supply”, as shown and described.